US Bridges

Or 99W (hwy 1W) over Flat Creek

Fair

Lane County, Oregon · 02.4 N JCT HWY 229 · Structure no. 03945 01W 10890

Built
1947
78 years old
Condition
Fair
inspected January 2024
Type
Slab
Concrete Continuous
Length
156 ft
8 main spans
Daily traffic
18,004
2022 count
Owner
State
State Highway Agency

About this bridge

Or 99W (hwy 1W) over Flat Creek is a concrete continuous slab carrying Or 99W (hwy 1W) over Flat Creek in Lane County, Oregon. It was built in 1947, so it is 78 years old, older than the Oregon average of 49.9 years.

The most recent inspection reported to the Federal Highway Administration rates it in fair condition with a lowest component rating of 6 out of 9. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

It carries about 18,004 vehicles a day, roughly 6% of them trucks, projected to reach 18,100 by 2042. The structure is 156 ft (47.5 m) long and 70 ft wide. If it were closed, the detour would be 17.4 mi (28 km).

Location

Open in Google Maps
CarriesOr 99W (hwy 1W)
CrossesFlat Creek
Location02.4 N JCT HWY 229
RouteState Highway 99
CountyLane County
StateOregon
Coordinates44.22741, -123.20507
Functional classRural Minor Arterial

Condition and inspection

Fair

The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

ComponentRatingMeaning
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection7 GoodSome minor problems.
Last inspectionJanuary 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourUnknown foundation; not evaluated for scour
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating34.3 US tons
Inventory rating26.5 US tons

Structure

Structure typeSlab
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans8
Design loadHS 20
Structure length156 ft (47.5 m)
Longest span19 ft (5.9 m)
Deck width70 ft (21.4 m)
Roadway width58 ft (17.7 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic18,004 (2022)
Projected traffic18,100 by 2042
Trucks6%
Lanes on structure4
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed17.4 mi (28 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was Or 99W (hwy 1W) over Flat Creek built?

It was built in 1947, making it 78 years old in 2025.

What condition is Or 99W (hwy 1W) over Flat Creek in?

The National Bridge Inventory rates it in fair condition. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound. The last reported inspection was in January 2024.

How much traffic does Or 99W (hwy 1W) over Flat Creek carry?

About 18,004 vehicles per day (2022 count), of which roughly 6% are trucks.

How long is Or 99W (hwy 1W) over Flat Creek?

The structure is 156 ft (47.5 m) long with a longest span of 19 ft (5.9 m) and a deck 70 ft wide.

Who owns Or 99W (hwy 1W) over Flat Creek?

It is owned by the State Highway Agency.